The main purposes of this study are: (a) describe the nature and extent of sleep medication use among elderly men and women residing in 18 skilled nursing facilities; (b) determine the relationship between the rate of nurse administration and various medical, social, psychological, and situational factors that may influence nurse decision-making; and (c) determine whether and how nursing home ownership is related to the administration of sleep medications. The theoretical framework considers both social and medical factors, including: patient characteristics, the level of patient demand for medication, nurse attitudes toward sleep medications and their use in nursing homes, nurse-patient ratios, drug type and schedule, and nursing home ownership. Six types of data will be collected and analyzed by multidisciplinary team that includes a medical sociologist, a physician, two pharmacists, and a sociologist-social worker. The sources of data include: pharmacy record data, data from medical/nursing records, a nurse questionnaire, systematic observation of evening nurses, a post-observational interview with the nurse, and a survey of nursing home administrators. Since there are few scientific studies that examine nurse decision-making regarding sleep medication, this study should be of considerable interest to members of various health professions as well as specialists in gerontology and medical sociology.